1. Field of the Art
This invention relates to method and apparatus for scrubbing work in a running wash liquid, especially suitable for washing and scrubbing articles of substantially flat disc-like shapes such as magnetic disc substrates including glass substrates and other ceramic substrates, and various electronic, optical or mechanical parts of such shapes.
2. Prior Art
Scrubbers which are arranged to wash work of flat shapes like magnetic disc substrates by the use of scrubbing brushes have been known in the art, for example, from Japanese Laid-Open Patent Specification S61-8734 and Japanese Utility Model Publication H4-22411.
Generally, prior art scrubbers of this sort are provided with spray nozzles thereby to spray a shower of wash liquid on work pieces while being washed and scrubbed by the scrubbing brushes.
Washing work pieces in a shower of a wash liquid which is sprayed from a spray nozzle or nozzles is effective as long as contamination of work is relatively light and of such a degree as would not require supply of a large amount of wash liquid. However, a wash liquid spray nozzle or nozzles of this sort normally can spray only a limited amount of wash liquid and therefore are not necessarily suitable for use in scrubbing relatively heavily contaminated articles which need a large amount of wash liquid supply to wash away deposited contaminants in an assured manner without permitting once removed contaminants to re-deposit on scrubbing brushes, as in the case of buffing work pieces which still bear abrasive powder or other foreign matter deposited in an immediately preceding machining operation or operations.
Besides, the wash liquid spray nozzles have to be enclosed in a hood or other splash guard means in order to block splashes of the wash liquid which tend to scatter around a scrubbing apparatus considerably especially in a case where a large amount of wash liquid is spurted and hit against work pieces at a high velocity.